Proceedings of the Geologists Association最新文献

{"title":"Palynological and palaeoenvironmental assessment of a fluvio-marine transition zone: An example from the Barremian of Northern Egypt","authors":"Aya Raafat,&nbsp;Doha Emad,&nbsp;Selim S. Selim","doi":"10.1016/j.pgeola.2026.101208","DOIUrl":"10.1016/j.pgeola.2026.101208","url":null,"abstract":"<div><div>The current study provides further insight into the palynological characteristics of the Alam El Bueib Formation, which is considered a valuable rock unit for the oil industry. Although the clastic facies of the Alam El Bueib rock unit make it difficult to determine its age, the examined interval of Alam El Bueib is characterised by relatively rich organic matter that helps the assessment of its age, palynologically. A comprehensive palynofacies investigation was carried out on thirty-nine cutting samples from the lower Cretaceous succession in three wells, north Western Desert, Egypt. Qualitative and quantitative palynological assessments produce 31 species belonging to 25 genera of palynomorphs. The identified spore, pollen and dinoflagellate cyst species have a clear affinity to the Barremian age. Visual and cluster assessment of the stratigraphical variation in the palynofacies suggests two compositionally distinct palynofacies assemblages. The palynofacies analysis was performed to explain the change of the dispersed organic matter and the related depositional environment. The palaeoenvironmental interpretation of the studied succession suggests that the basal part of the Alam El Bueib Formation was formed during a period of marine regression in a fluvio-deltaic environment, whilst the upper part shows a slightly deeper condition, represented by a marginal marine environment. These findings enhance the understanding of the fluvio-marine transition zone and its implications for palaeoenvironmental reconstruction and hydrocarbon potential in the region.</div></div>","PeriodicalId":49672,"journal":{"name":"Proceedings of the Geologists Association","volume":"137 4","pages":"Article 101208"},"PeriodicalIF":1.2,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148647212","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reconstructing the Variscan orogeny in the Pontides: New U–Pb zircon ages and Sr–Nd isotopes from folded basalt dykes in the İstanbul–Zonguldak Tectonic Unit","authors":"Fatih Şen,&nbsp;Serdal Karaağaç,&nbsp;İsmail Onur Tunç","doi":"10.1016/j.pgeola.2026.101202","DOIUrl":"10.1016/j.pgeola.2026.101202","url":null,"abstract":"<div><div>The İstanbul–Zonguldak Tectonic Unit (NW Turkey) has long been regarded as a continental fragment of Far East Avalonia, traditionally interpreted as a magmatically inactive arc during the Carboniferous. New U–Pb zircon ages, whole-rock geochemistry, Sr–Nd isotopes, and structural data from basalt dykes in the western sector of the İstanbul–Zonguldak Tectonic Unit in Pontides provide new constraints on Late Paleozoic tectonomagmatic evolution in the peri-Gondwanan domain. The dykes intrude pre-Silurian sedimentary rocks and yield concordant Late Carboniferous crystallisation ages (<em>c.</em>, 323.6 ± 0.5 Ma and 310.7 ± 2.9 Ma), whilst Early Permian zircon overgrowths (<em>c.</em>, 293–281 Ma) record a post-emplacement tectono-thermal event. Geochemical and isotopic signatures (calc-alkaline affinity, negative Nb anomalies, εNd(i) = −<!--> <!-->3.9 to −<!--> <!-->5.7) indicate subduction-related arc magmatism sourced from an evolved crustal component. Field data reveal that the dykes are folded along NE-trending axial planes that align with Variscan folds documented in the host rocks, suggesting deformation during the Early Permian. These findings suggest a need to reconsider earlier models that proposed an Early Carboniferous collision between the İstanbul–Zonguldak Tectonic Unit and the Sakarya Terrane. Instead, a diachronous arc–arc collision model is proposed, in which the Rheic Ocean subducted beneath Far East Avalonia until the Late Carboniferous, and final collision with Minoan-derived Sakarya occurred in the Early Permian. This redefines the timing and nature of the Variscan orogeny in the eastern peri-Gondwanan margin.</div></div>","PeriodicalId":49672,"journal":{"name":"Proceedings of the Geologists Association","volume":"137 4","pages":"Article 101202"},"PeriodicalIF":1.2,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148647209","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Miocene vertebrate footprints from the Eastern Paratethys deposits of the southern Caspian, Northern Iran","authors":"Nasrollah Abbassi,&nbsp;Reza Emamgholi,&nbsp;Javad Rabbani,&nbsp;Abdolreza Moghaddasi,&nbsp;Mohammad Saeed Shariatzadeh","doi":"10.1016/j.pgeola.2026.101199","DOIUrl":"10.1016/j.pgeola.2026.101199","url":null,"abstract":"<div><div>Cenozoic vertebrate footprints provide critical insights into the palaeobiogeography of the Eastern Paratethys region. Here, we report a newly discovered Miocene tracksite from the southern coast of the Eastern Paratethys basin in Mazandaran Province, northern Iran. The site, located along the eastern ridge of the Shahid Rajaei Dam, preserves multiple layers containing mammal and bird footprints within alternating mudstone, siltstone, and sandstone layers. The presence of Miocene planktonic foraminifera supports a Sarmatian age for these layers. Eighteen mammal footprints and numerous bird tracks were documented, attributed to the proboscidean ichnospecies <em>Proboscipeda panfamilia</em> and the tridactyl bird ichnogenus <em>Uvaichnites</em> isp. Footprints display concave epirelief morphology, digit impressions, and trackway patterns consistent with Miocene faunas. A comparative review indicates low ichnotaxonomic diversity at this site relative to other Eastern Paratethys localities but confirms the presence of large terrestrial vertebrates in northern Iran. These findings extend the geographic distribution of Miocene proboscidean and avian tracks along the southern Eastern Paratethys coast and contribute to understanding faunal dispersal, vertebrate ichnodiversity, and the palaeoenvironmental evolution of the region. This tracksite, together with other Eastern Paratethys and southern Carpathians–Pontides–Alborz–Kopet Dagh vertebrate records, highlights the role of tectonic barriers in shaping endemic terrestrial vertebrate assemblages.</div></div>","PeriodicalId":49672,"journal":{"name":"Proceedings of the Geologists Association","volume":"137 4","pages":"Article 101199"},"PeriodicalIF":1.2,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148647207","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Lower Cretaceous oyster reef (Cinder Member, Purbeck Limestone Group, Dorset, southern England): biotic response to co-seismic sea-level rise?","authors":"Jonathan D. Radley,&nbsp;Robert A. Coram","doi":"10.1016/j.pgeola.2026.101206","DOIUrl":"10.1016/j.pgeola.2026.101206","url":null,"abstract":"<div><div>The Berriasian (Lower Cretaceous) Cinder Member (Durlston Formation, Purbeck Limestone Group) in south Dorset, southern England (Portland–Wight Basin) is an oyster-rich brackish-water horizon deposited as a biostromal reef complex within linked half-grabens immediately south of the Purbeck–Ridgeway fault system. It is well exposed in coastal sections between Durlston Bay, Swanage and Durdle Door, where its relative thickness and abrupt appearance above lacustrine lithofacies indicate rapid deepening and marine transgression, promoting reef establishment close to the northern margin of the Purbeck lagoon. We suggest that the marked increase in accommodation space demonstrated by this outcrop was due to movement on the Purbeck Fault, which was evidently active during Berriasian times. Cinder Member developments documented elsewhere in the southern English Wessex and Weald basins are potentially asynchronous, though deposited against a common backdrop of substantial marine influence within a basin-wide lagoonal complex, close to sea level.</div></div>","PeriodicalId":49672,"journal":{"name":"Proceedings of the Geologists Association","volume":"137 4","pages":"Article 101206"},"PeriodicalIF":1.2,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148647213","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bartoncetus wanklyni, new genus of a small dorudontine whale from the Bartonian of England; a lost skull and a forgotten postcranial skeleton","authors":"Henk Jan van Vliet,&nbsp;Jonas Hakkens,&nbsp;Theo M. Paijmans,&nbsp;Charles J. Underwood,&nbsp;Ivo Verheijen,&nbsp;Mark E.J. Bosselaers,&nbsp;David J. Ward,&nbsp;Dirk K. Munsterman,&nbsp;Jelle W.F. Reumer","doi":"10.1016/j.pgeola.2026.101201","DOIUrl":"10.1016/j.pgeola.2026.101201","url":null,"abstract":"<div><div>Since 1913, the Bournemouth Natural Science Society has housed a partial postcranial skeleton, regarded as a small archaeocete whale from the Barton Clay Formation at Highcliffe and Barton-on-Sea, England. Despite being mentioned at least once in literature, it has never been thoroughly described. In 1876, Seeley described a small basilosaurid skull from the same location and formation, naming it <em>Zeuglodon wanklyni</em>; illustrations were not provided by him. Later, Kellogg (1936) reclassified it as <em>Zygorhiza wanklyni</em> Seeley, 1876. Unfortunately, the skull was lost soon after its discovery. Traditionally, small basilosaurid remains from Barton-on-Sea cliffs have been assigned to ‘<em>Zygorhiza</em>’ <em>wanklyni</em>, but this name is now generally regarded a <em>nomen dubium</em>. The skeleton, newly described here, provides an opportunity for re-evaluation of this taxon. Both the skeleton and skull can be attributed to a juvenile, small dorudontine basilosaurid, apparently representing the same taxon, comparable in size to a juvenile <em>Dorudon atrox</em> Andrews, 1906. Based on several unique features, we establish a new genus, <em>Bartoncetus</em>. Similar remains have been discovered in the Helmstedt region of Germany, part of the same Eocene North Sea Basin, and possibly also in Varano, Italy. Based on dinocysts in the adhering sediments, the partial skeleton has been dated to 39.5 to 40.5 Ma, <em>i.e.</em>, during the middle Bartonian, the middle Eocene. This makes it one of the oldest, well-dated remains of a small dorudontine basilosaurid currently known.</div></div>","PeriodicalId":49672,"journal":{"name":"Proceedings of the Geologists Association","volume":"137 4","pages":"Article 101201"},"PeriodicalIF":1.2,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148647210","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"U–Pb age constraint on rhyolite and volcaniclastic layers associated with Paleozoic strata from the Loei Fold Belt, NE Thailand","authors":"Mongkol Udchachon,&nbsp;Xin Qian,&nbsp;Hathaithip Thassanapak,&nbsp;Peter Königshof","doi":"10.1016/j.pgeola.2026.101207","DOIUrl":"10.1016/j.pgeola.2026.101207","url":null,"abstract":"<div><div>The area of Thailand and neighbouring countries has a complex tectonics, and we report age-dating of volcanic and volcaniclastic rocks in a critical area that provides new insights into the geological history. In the Loei Fold Belt of the Indochina Terrane, volcanism is recorded from Late Ordovician to Triassic. Zircon U–Pb (LA-ICP-MS) dating of rhyolitic tuff underlying conodont-bearing late Silurian to earliest Devonian limestone indicates another major eruption in the middle Silurian (433 ± 4 Ma). This event forms part of the same volcanic eruptive series that occurred 16 Ma earlier, as reported farther north in Laos. The subsequent major eruptions took place from latest Early Devonian to Middle Devonian age (398 ± 6 and 385 ± 2 Ma). Rhyolitic tuff intercalated with Upper Devonian siliceous shale and chert is younger (381 ± 3 Ma). Middle Devonian shallow marine carbonates and stromatoporoid–coral build-ups formed on volcanic edifices during volcanic quiescence. Conodonts from micritic limestone underlying the reef confirm a Givetian age, consistent with zircon U–Pb ages of volcanic rocks, and support the previous interpretation that the deposition basin was proximal to the contemporary continental arc environment. However, a rhyolitic dyke that intruded Upper Devonian chert and Carboniferous limestone is of late Lower to early Middle Triassic (250 ± 4 and 243 ± 3 Ma). Previous geochronology and geochemistry works and our zircon U–Pb age rhyolite and volcaniclastic layers associated with Paleozoic marine strata indicate that the western part of the Indochina composite terrane was an active margin during Ordovician to Triassic.</div></div>","PeriodicalId":49672,"journal":{"name":"Proceedings of the Geologists Association","volume":"137 4","pages":"Article 101207"},"PeriodicalIF":1.2,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148647211","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Silurian (Gorstian) terrestrialisation records in the Red Cliff Formation of Pembrokeshire, UK: the oldest Old Red Sandstone in England and Wales","authors":"Robert D. Hillier ,&nbsp;Kenneth T. Higgs","doi":"10.1016/j.pgeola.2026.101180","DOIUrl":"10.1016/j.pgeola.2026.101180","url":null,"abstract":"<div><div>The Red Cliff Formation preserves an important record of terrestrialisation. Palynomorphs date the base of the Formation as no older than late Homerian, with palynomorphs within it comprising the <em>Apiculiretusispora</em>? <em>asperata</em> Subzone which spans the late Gorstian/early Ludfordian.</div><div>The Formation contains proximal to distal lithofacies variations of a low gradient dryland alluvium and contemporaneous delta plain bordering the Lower Paleozoic Welsh Basin. Drainage networks contained through-going to discontinuous alluvial channels characterised by declining downstream dimensions, seasonal discharge patterns and intervals of low/no flow and prolonged desiccation. Rivers flowed to the north, north east and east. Trunk channels deposited sandstone-dominated inclined heterolithic stratification (IHS) in proximal reaches transitioning into mudstone-dominated IHS in distal, and marginal secondary channel zones comprising a muddy braid plain of anastomosing channels built from mud aggregates. Flat-bedded heterolithic units were deposited in intermittent, ephemeral wetlands located in channel waterholes or floodplain floodouts. Extreme flood events diverted sand-grade material from trunk channels through avulsion/crevasse channels, depositing high width-to-depth sheets. The drainage network was subject to Vertisol pedogenesis. Spore preserving, tidal IHS and tidal flat lithofacies associations are preserved at the fluvial–marine transition.</div><div>Mudstone-rich alluvial deposits contain <em>Beaconites antarcticus</em>, <em>Planolites</em> and <em>Thallasinoides</em>-like burrows produced by opportunistic colonists. Fluvial–marine transition environments preserve a low diversity assemblage comprising <em>Lingulichnus</em>, <em>Skolithos</em>, <em>Planolites</em>, <em>Lockeia</em> and less common <em>B. antarcticus</em> and <em>Treptichnus</em>. <em>Phycosiphon</em> burrows preserved in the fluvial–marine transition and some alluvial environments indicate elevated salinities and landward migration of brackish water sufficient to maintain opportunistic, amphidromous marine infaunas during low discharge intervals.</div></div>","PeriodicalId":49672,"journal":{"name":"Proceedings of the Geologists Association","volume":"137 3","pages":"Article 101180"},"PeriodicalIF":1.3,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148193582","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A second specimen of the enigmatic Wealden reptile Yaverlandia","authors":"Darren Naish ,&nbsp;Steven C. Sweetman","doi":"10.1016/j.pgeola.2026.101179","DOIUrl":"10.1016/j.pgeola.2026.101179","url":null,"abstract":"<div><div>The enigmatic Early Cretaceous reptile <em>Yaverlandia bitholus</em> – conventionally interpreted as a dinosaur – was, until recently, known from a single specimen comprising a partial skull-roof from the Lower Cretaceous (Barremian) Wessex Formation of Yaverland on the south-east coast of the Isle of Wight, southern England. It possesses two low, fused and thickened, domed frontals and possession of these was originally used to justify assignment to the ornithischian dinosaur clade Pachycephalosauria. More recent studies have questioned this assignment. We report a second specimen, more abraded than the holotype but comprising almost the same section of skull. It confirms that swellings on both frontals are a normal feature of this taxon. <em>Yaverlandia</em>'s affinities remain unresolved and better remains are required before any identification can be considered secure. However, the tradition of considering <em>Yaverlandia</em> a dinosaur is connected to its initial misidentification as a pachycephalosaur and it may prove to be non-dinosaurian entirely. The fact that only two <em>Yaverlandia</em> specimens – discovered 89 years apart – are known may indicate genuine rarity of this taxon, or its specialisation for a rarely sampled habitat.</div></div>","PeriodicalId":49672,"journal":{"name":"Proceedings of the Geologists Association","volume":"137 3","pages":"Article 101179"},"PeriodicalIF":1.3,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148193568","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Structural controls and palaeostress analysis of hydrothermal circulation and fluorite–baryte ore genesis at Jbel Merguechoum, Moroccan Eastern Meseta","authors":"Cherai Mohammed ,&nbsp;Benamrane Mohammed ,&nbsp;Rddad Larbi ,&nbsp;Talbi Fouad","doi":"10.1016/j.pgeola.2026.101188","DOIUrl":"10.1016/j.pgeola.2026.101188","url":null,"abstract":"<div><div>The Jbel Merguechoum fluorite–baryte ore is hosted in Late Hercynian granite, situated beneath the Paleozoic–Triassic unconformity in the Moroccan Eastern Meseta. This deposit represents a key example of rift-related hydrothermal mineralisation. This study integrates detailed structural mapping and palaeostress analysis to evaluate the role of fracture systems in ore genesis and to constrain the relative timing of mineralisation. The fluorite–baryte ore is spatially associated with NNE–SSW to NE–SW normal faults, NE–SW tension gashes, and minor NNW–SSE normal faults that were reactivated during Triassic–Jurassic extension. Palaeostress reconstructions indicate an extensional regime with a subvertical σ1 and a subhorizontal NNW–SSE σ3. This configuration generated crustal-scale normal faults that enhanced permeability. During the Triassic–Jurassic rifting related to the breakup of Pangea, marine basins developed, providing a source of seawater that infiltrated deeply along these active structures. This tectonic-structural model underscores fault reactivation and rift-induced convection as critical ore-forming processes, providing insights for the exploration of unconformity-related deposits in extensional settings.</div></div>","PeriodicalId":49672,"journal":{"name":"Proceedings of the Geologists Association","volume":"137 3","pages":"Article 101188"},"PeriodicalIF":1.3,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148193583","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enigmatic lineations in the Strait of Dover may be glacial","authors":"Julian B. Murton ,&nbsp;David J.A. Evans ,&nbsp;Sanjeev Gupta","doi":"10.1016/j.pgeola.2026.101186","DOIUrl":"10.1016/j.pgeola.2026.101186","url":null,"abstract":"<div><div>The maximum limit of Pleistocene glaciation mapped offshore of the British Isles is strikingly asymmetric, extending more than 200 km farther south in the Celtic Sea and western English Channel than in the North Sea. To determine if this asymmetry is real, we evaluate high-resolution sonar data of the seabottom topography in the Strait of Dover. In the central Strait, parallel lineations in the form of grooves and ridges cut in chalk bedrock are 30–1000 m long and 3–43 m wide, with elongation ratios of 1.4–333 and amplitudes of 0.1–2 m (García-Moreno et al., 2021). In plan form, the lineations display remarkably parallel orientations and range from straight-sided grooves and ridges of largely consistent width to tapering or spindle shapes of variable width. The potential origins of the lineations as products of geological structure, megaflood erosion, marine erosion, aeolian erosion or periglacial processes are rejected on morphometric and theoretical grounds. Instead, the lineations are interpreted as megascale glacial lineations (MSGLs) attributed to subglacial erosion by a palaeo-ice stream flowing southwestwards from the southern North Sea Basin to the Strait of Dover. The age of this glaciation is probably Anglian (Marine Isotope Stage (MIS) 12), although a late Wolstonian (MIS 6) or MIS 16 age cannot be discounted.</div></div>","PeriodicalId":49672,"journal":{"name":"Proceedings of the Geologists Association","volume":"137 3","pages":"Article 101186"},"PeriodicalIF":1.3,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148193588","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}